Thanks for the self-contained example. This is probably related to the class of REPL bugs that can be worked around by passing the -Yrepl-sync option. Unfortunately, I don't think there is a way to modify the settings used by ILoop.break. I don't think this particular issue has been raised, so you should open a bug on the Scala issue tracker (but still check that it isn't covered by an existing bug).
-Mark
> -schone
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